The FTSE 100 closed at 7,292.37 on Thursday, after squeezing out a 0.03 per cent rise.
The index has now registered 11 record closes in a row, driven by a weaker pound, higher commodity prices and better than expected company results.
Stocks managed to break through the 7,300 mark for the second day in a row, with mining stocks among the biggest risers.
A spate of retailer updates this week have painted a positive picture of Britain's economy over Christmas, with Marks and Spencer among the companies that have beat expectations over the festive seasons.
But a rise in sterling and Donald Trump's press conference have helped to subdue activity.
The President-elect suggested he would take action against drug companies and their pricing policies.
Michael Hewson, chief market analyst at CMC Markets UK, said: "One of the main drags has been weakness in the health care sector driven by last night’s comments by US President elect Donald Trump with respect to their pricing policies.
"His remarks that the companies had been getting away with murder with respect to pricing at a time when drugs prices have been rising is likely to raise concerns that he may take steps to curb these companies’ ability to charge the prices they want to.
"Shire Pharmaceuticals and Hikma are down near the bottom of the index."
He added: "Basic resource stocks have continued their recent resilience with another positive day driven by strength in commodity prices with gold prices jumping to their highest levels since November, above $1,200 an ounce.
"Firmer copper and iron ore prices have also helped pushing Rio Tinto, Fresnillo and Randgold Resources to the top of the FTSE 100."
And experts believe the FTSE could continue to post gains in the coming months.
Laith Khalaf, senior analyst at Hargreaves Lansdown, said: "It’s not just the miners and international companies benefiting from lower sterling which are sustaining the rally, some domestically-focussed stocks are also chipping in, which suggests some optimism towards the prospects for UK companies is driving the market upward too.
"It’s important not to get too carried away with the recent run of good form.
"Over such a short time frame it’s best to take stock market movements with a pinch of salt, whether they are good or bad.
"If you’re invested in the stock market, as most people are through their pension or ISA, then the crucial thing is what the market delivers over the long term, and that’s really where you get the very best returns from stocks compared to other assets."